Mitral Valve Prolapse

Billowing leaflets as seen from the left atrium.

 Irregular, redundant, billowing mitral leaflets. A valve of this type is usually associated with moderate to severe mitral regurgitation.

Common in young women. One or both leaflets is (are) enlarged, hooded or tent-like, and floppy; sometimes thick and rubbery. Prognosis is very good overall but MVP may lead to serious complications which include infective endocarditis, mitral regurgitation, emboli from thrombi on the valvular or atrial mural endocardium, or serious atrial or ventricular arrhythmias. Pathologically, in addition to thick, rubbery leaflets, the chordae tendineae are elongated, thin, and prone to rupture. The mitral annulus dilates. The commissures do not fuse. The lamina fibrosa becomes thin and there is multifocal marked thickening of the spongiosa with deposition of mucoid material. Marfan syndrome, a disorder secondary to missense mutations in the fibrillin gene, and other hereditary disorders of connective tissue are responsible for some cases of MVP. Further research will probably discover other genetic bases for MVP.